Means for governing the rolling of ships



E. A. SPERRY MEANS FOR GOVERNING THE ROLLING OF SHIPS Apr. 17, 1923.

5 Sheets-Sheetl Filed Sept. 30 1916 3 0 1m] Hill I11 I [C lllll Fla 2,

' INIVEN-TOIR. [LMER A. SPERRX I A TTORNZX Fla 3.

E. A.. SPERRY MEANS FOR GOVERNING THE ROLLING 0F SHIPS Apr. 17, 1923.

Filed Sept. 30 1916 s Sheets-Sheet 2 Fic. 4.

[LA ERA SPERM I Arm/1dr] Apr. 17, 1923. 1,452,482

E. A. SPERRY Y MEANS FOR GOVERNING THE ROLLING OF SHIPS Filed Sept. 30 1916 3 sheets-Shem s mmvror;

ELMER A. SPERRY BY 1 ATTOR/VFX .Patented Apr. 17, 1923.

vsidin of war vessels- In my UNITED, STATES PAi-"EN '15 OFFICE.

- magma a SPERRY, or BROOKLYN, NEW YORK, assrenon T srmmr eyaoscorn courm, or BROOKLYN, NEW YORK, A CORPORATION or NEW YORK.

MEANS FOR GOVERNING ROLLILIG OF S HIPS.

Application filed September 30, 1916. Serial No. 128,155.

To all whom it may concern:

'Be it: known that I, ELMER A. SPERRY a citizen of the United States of America, re-

at 1505 Albermarle Road, Brooklyn, New ork, in the county of Kings and State of New York, have invented certain new and useful Improvements in Means forGoverning the Rolling of Ships, oiwhich the following is a specification. r This invention relates to means for governing themotion of ships at sea and has especial reference to controlling the rolling patent on ships gyroscopes, No. 1,150,311, granted Aug. 17, 1915, and on ship stabilizingand rolling apparatus, No. 1,232,619, ranted J uly 10, 1917 ,.I

- show an apparatus'w ich may be used either to stabilize or rolla ship or similar unstable vehicles. One of the main objects of this invention is to improve upon apparatus of this character and to adaptjit especially to the needs of ships of war. The primary purpose of a battleship is to shoot straight. It has long been appreciated that the rolling and pitching of the ship very seriously impair the effectiveness of gun fire. In studying th'echaracteristics of rolling, it has been found that when vessels, such as battleships and cruisers, roll less than a certain amount, the roll is attended with certain peculiarities, or idiosyncracies.

The roll is foundto be fitful and not dependable, the shipgenerally rolling twice and sometimesthree times in the same direction before rolling back. Therefore it cannot'be relied upon in attempting to anticipate the laying of ordance in'elevation for the most effective gunnery. Beyond this critical point in the amplitude of roll "of a ship'however, true periodicity permanently sets in and becomes therefore'perfectly dependable. When thischaracteristic roll is present, it is found that ordnance may be accurately laid in elevation, and if some device were provided, whereby the amplitude may be held constant, then nochange need be made in the elevation of the guns, except 'for change of range. Thus the new system ed director firing, that is,'fir1ng'all guns'simultaneously at a certain predeterof so-cal mined pointof the oscillation due to the roll- -ing can be brought to a very much higher degree of perfection than ever possible before.-- i 1' e specific object of the invention, then,

. scopes.

' is to devise'an apparatus for accomplishing this purpose. To this end, I have improved upon and adapted the gyroscopic apparatus disclosed in the above mentioned patents. Another object of the invention is to insure the firing of the unsat the proper-point in 3 the period of the roll of the ship.

Referring to the drawings in which, what I now consider to be the my invention are'shown: 1

Figure 1 is an elevation of the master or control gyroscopes.

Figure 2 is a plan view thereof. Figure 3 is a plan view on a much smaller scale of the main stabilizing gyroscopes, also showing diagrammatically the control gyroscopes and .the wiring connections between them and the stabilizing gyroscopes.

of both the control and stabilizing gyroscopes. metry, the scale of the control larger than that used gyroscopes.

Figure 5 is a sectional view of one of the valves used in this form of invention.

Figure 6 is a sectional view of a' relay valve controlled thereby.

Figure 4 is a plan view of a modified form v I gyroscopes is for the stablllzing preferredqforms of In this view, for the sake of sym- Figure 7 is a section on line'7 7, Fig. 4 F

von an enlarged scale; Figure 8 is;a wiring diagram showing the connections for utilizing my device to control the firing of the guns.

- Figure 9 is a detail of the master gyro- According to this invention, a device which is responsive to the rolling used as a master governor. This device is somewhat similar in its action to a 'pendulum and consists preferably of one or more gyroof the ship is scopes, 1 and-2. These gyroscopes are shown Y mounted on horizontal vertical rings 3 and 4. The rings in turn are pivoted about vertical pivots 5 and 6, within fixed bearing rings 7 and 8. The rings 3 and 4 are coupled for equal and opposite turning about vertical axes by means such as a link 9, pivoted to brackets 10 and 11, extending from said 'rings. The gyroscopes are mounted on the ship with their spinning axes athwartship (see fore and aftlline. 12 Figure 2), so-that the rolling of the ship will cause precemion I of the gyroscopes about their vertical axes 5 and 6. The gy-v roscope's are preferably centralized by means spinning axes within of compression springs 13 and 14 which bear against pins 16 and 16', slidably mounted in fixed brackets 15 and 115. A lug 17 extending from ring 4 is adapted to strike either one or the other of pins 15 and 15' when the gyroscope precesses. Preferably a small space is left between the ends of the pins and said lug for purposes hereinafter described. A fixed contact piece 18 is shown attached to vertical ring 3 and is adapted to strike on precession of the gyro, either one or the other of adjustable contacts 19, or 19'. These contacts control the stabilizing or rolling means for the ship.

Also projecting from said ring 3 isshown a member 20, yieldingly held between a pair of pivoted arms 21 and 22. The arms may be geared together as by means of gears 23 and are yieldinglypressed toward each other by means of a spring 24. The piston 25, of.

a dashpot 26 is pivotally connected to a rod 227 extending from one arm so that after being opened the return of the arms 21 I and 22 to their closed position underthe inthe contacts 18 and 20are' applied to control the stabilizing or rolling apparatus. If the ship is rolling less than the predetermined amount, the contacts are so arranged as to increase the rolling. If, on the other hand. the ship rolls more than the predetermined amount, the arms 21 and 22 will be opened sufiiciently to complete contacts 27 and 28, which, by means such as hereinafter -de..

scribed, reverses the action of the contacts so that the stabilizing or rolling appa ratus will then begin to quench the rolling of the ship. Said stabilizing or rolling apparatus preferably consists-of one ormore large gyroscopes 31 and 32, firmly secured to the ship.

s -Apparatus of this kind, performing as it does, a double function, may be termed a means for exerting periodic rolling torques on the ship since no matter-whether it is rolling or'stabilizingthe ship. it exerts said torques, the only difference being that in the former case the torques are in synchronism .avith. the roll while in the latter they are displaced 180 in the cycle. The gyroscopes are shown as mounted on horizontal spinning axes 33 and 34 within casings 35,35 which are pivotally mounted about vertical axes 36, 36' to the frame work 37 of the ship. I The gyro- -scopes are adaptedto be spun in opposite directions and are placed with their spin- ,ning axes athwart-ships as indicated by arL.

row 38. The gyroscopes are coupled for equal and opposite precession by means of gears 39 and 40. The power for controlling these gyroscopes from the master gyro may be furnished by a motor 41, which drives continuously .in opposite directions a pair of beveled gears 42 and 43 loosely mounted upon shaft 44. A clutch 45 is adapted to be thrown into engagement with a clutch face 46 on either of said gears so as to drive the shaft 44 in either direction.' Said clutch is controlled by means of a plurality of electromagnets 47 and 48, which are in circuit with orcontrolled from the control switches above referred to. Shaft 44 carries a worm 49 which meshes with a worm wheel 50. On

the shaft of said worm wheel is mounted a pinion'51 which connects it with gear 40 so that the motor 41 may exert torques about the preoessional axes of the two gyros.

When the device is operating toquench the rolling of the ship, the shaft 44 is driven in a direction to cause or permit precession of the gyroscopes in the natural direction caused by the rolling of the ship. When the ship first starts to' roll, the precession, gear will accelerate the precession, but after the rolling has started, the gyroscopes will tend to precess faster than the worm is turned by the motor so that the said worm acts as a brake on the gyroscopes. When the gyroscopes are acting to roll the ship, however, the shaft 44 is rotated in a direction to apply a torque on the gyroscopes in the opposite direction to the'natural precession caused by the rolling of the ship. In other words, the action of the precession gear is exactly reversed or displaced substantially 180 with respect to the rolling cycle. J

For efi'ecting this purpose, the contacts 27, 28 on gyroscope 1' (Fig. 3) are placed in circuit with an electro-magnet 150 which actuates the reversing switch 151 in the circuit between contacts 19 and 19' and magnets 47 and 48, so that as long as the ship .s exceeding a predetermined amplitude, the apparatus will act as a stabilizer, while when said limit is .not exceeded, the circuit through magnet 150 will be broken and switch 151 rotated by spring 152 to cause the apparatus to roll the ship. a

Preferably, I also provide in connection w'th my stabiliiing androlling' apparatus an automatic means whereby the guns or other ordnance appliances, such as torpedoes and the like, may be fired at predetermined periods in the roll of the ship. By securing -through my apparatus a perfectly definite amplitude and period of roll and by. providing an automatic apparatus for firing the guns at a redetermined point therein, ab? solute precision and timing of the fire may be obtained... This apparatus is preferablyincor orated as a part ofthe gyroscopes 1 .and 2. As above stated the centralizing and 131 adapted to strike other contacts 132 and 132, after a predetermined precession has taken place against the action ofthe centraliz'ng springs 13 and 14. The first pair of the above described contacts constitutes one method for firing the guns when the ship is at one or the other limits of its roll, that is, when the ship is starting to swing back on the reverse roll, since the moment the direction of roll changes the gyroscopes will start to precessin the other direct'on and hence move against the other contacts 130 or 130. Contacts 131 and 132,

on the otherhand, constitute a means for firing the guns when the ship reaches its maximum velocity of roll, which it will be readily understood is normally when it is passing through its horizontal position. As gyroscopes normally maintain a definite ampl'tude of roll, the position of contacts 130, 132 and the tension of springs 13 and 14 maybe nicely adjusted to fire the guns at the exact-maximum velocity since the torque exerted by the'gyroscopes on the springs due to their precession is directly proportional to theveloci'ty of roll. Other methods of securing" the above-results, other than by the'arran ment of contacts described, will suggest .t emselves to those skilled in the art.

Means for selecting the roper contacts and controlling the firing o the guns from the same is shown in Fig. 8. In this figure the switch-133 represents the firing button pushed by the Fire Control Oflicer. As this button is pressed into engagement with contact 134, it displaces the spring pressed catch. 135 so that the catch will snap over the button and hold it in engagement with contact 134 until withdrawn. An electromagnet 136 or similar means in circuit with the said button and the above described con connected through a double throw switch 137 which is designed to cut in a selected pair of contacts and at thesame time out out the other pair so that the guns may be fired when the ship is horizontal, or when it is at its maximum inclination, as desired. Another switch 138 may also be prov.ded which is designed to select which contact of the two contacts in each pair shall be used to fire the gun. In other words, these switches give the officer means for firing when the ship is passing thru its horizontal position either on the down roll or on the up roll and also when the guns are at either their maximum or m nimum elevation. If the ship were firing salvos from both sides at once it is quite conceivable 110w this apparatus could be made to fire the guns on each side when they are at their maximum elevation, in other words, so that a salvo would be discharged alternately from opposite sides of the ship twice during each roll of the sh'p. In the diagram, the fine platinum wires in the gun cartridges for firing the guns are shown at 140 and the source of electricity at 141.

My invention is, of course, adapted to be embodied in other forms than that shown and described above. For instance, motive fluids other than electricity may be employed to operatively connect the master and stabilizing gyroscopes. Such an embodiment of the invention is shown in Figs. 4 to 7 in which compressed air is employed. In Fig. 4 the master gyroscopes are again shown at 1 and 2 and the stabilizing gyroscopes at 31 and 32. Projecting from the vertical ring 4 of the gyroscope 2 is a bracket to which is attached a plurality of rods 61, 62, 63 and 64 all of whichare adapted to 'he moved axially by the precession of the gyroscope. Rods 64 and 63 are spring pressed so that they will centralize the gyroscope in a manner similar to pins 16 and 16 in the other form of theinvention. Ai ter a predetermined movement of rod 63 has taken place it will strike the valve rod 65 thereby effecting the displacement of the piston 66 within valve chamber 67-. A similar movement of rod 64 causes a similar action within the valve chamber 67. Rod 61 is connected to the piston 68 of piston valve 69 so that precession of the gyroscope 2'in either direction will displace the said piston. Said valve is connected to the main supply pipe 70 throughpassage 71 (see Fig. 7). Leading from said valve are two pipes 72, 73 which are connected to the reversing valve 74. Both of the valves 67 and 67' above described'are also connected to said Fig. 7

either pipe will move the piston to the opposite end.

The rod 62 is connected to another piston valve 82. Preferably a limited amount of lost motion is allowed between the rod 62 and the bracket in both directions. For this purpose the rod is provided adjacent its outer end with a slot 83 which engages over a pin 84 on bracket 60. The rod is normally centralized with respect to the pin by a pair of springs 85, and 86 which hear at the outer ends against fixed stops 87, 88, but at the inner ends against a member 89 pivotally secured to the end 90 of rod 62 (see The cylinder 82 is connected to the main supply through pipe 91 and ports 183 and 184 and is connected to a brake cylinder 93 mounted near the stabilizing gyroscope by means of pipe 94. Brake cylinder 93 is connected to an arm 194 pivoted at 95 to which is secured a brake band 96 extending entirely around the casing of gyroscope 31 within a guideway in or on brake drum 97. The brake is normally applied by means of the strong tension spring 98, but the cyl-- inder 93 is so designed'as to hold the brake oil when supplied with motive fluid. From theconstruction of valve 82, it will be apparent that the ports are open between the supply and the brake cylinder when the piston 182 is centralized. But when rod 62 is displaced the inlet ports 180 and 183 (or 181 and 184) willbe closed, shutting oil the main supply and at the same time opening exhaust ports 185 or 186, as the piston moves out from under them. This will at once reduce the pressure in the cylinder 93 and permit spring 98 to apply the brake. In the other form of the invention, the function performed by brake cylinder 93 is accomplished by means of a solenoid 93 in circuit with contacts 155 and 156 on the control gyroscopes. When'trolley 155 rolls beyond the end of contact 156, the brake is applied.

The piston of cylinder 79 is connected bymeans of-rod '99 to an arm 100 secured to a segmental gear 101. Also secured to said arm 100 is link 202 pivoted adjacent one end to a spindle block 203. Asecondl nk 104 is also secured to said block and is pivoted near its outerend to a bell crank lever 105. A similar bell crank lever 106 is joined thereto by adjustable link 107. Block 203 is normally centralized by means of compression springs 108, 109, which bear adjacent their inner ends against said block and adjacent their outer ends against stops 110 and 111. When the piston in the cylinder 79 is actuated it will not only rotate the gear 101, but will also rock bell crank levers 105, 106 in one direction or the other. A lug or stop 112 on the "casing of gyroscope 31 is adapted to strike one or the other of cam surfaces 113 or 113 on levers and 106 when either of them is rocked downwardly so that the the casing 103 as to shift said gearing to transmit motion from the constantly driven motor 41 to shaft 44 from the maximum speed in one direction through zero to the maximum speed in the opposite direction. I prefer to employ in this connection the transmission gearing known as the Vaterbury change speed gear, which is now employed for controlling the movements of gun turrets on warships. Shaft 44' is connected to the gyroscopes by means of worm 49, worm wheel 50, pinion 51 mounted on the shaft of the worm Wheel and the large gear 40 on the gyroscope 31.

The action of thecompressed air or hydraulicsystem above described is as follows Let us suppose first that the ship is rolling less than the predetermined amount and that the gyroscopic system is actin to increase the roll of the ship. In this position the valves 67, 67 will remain closed while valve 69 would be moved first in one direction and then in the other by the precession of the gyroscopes. The movement of piston 68 would cause air to flow from port 71 alternately into ports 116 and 120 as the piston reverses. I This would cause air to flow through pipe 72 into port 112 of valve 74 and from thence'out port 113 through pipe 78 to one end of cylinder 79.

Similarly when piston valve 68 moves in the other direction, air will flow through port 120 and pipe 73 into port 121 of cylinder 74 and from thence through the recess in the piston valve .and port 122 into pipe 77 which leads to the opposite end of cylinder79. It will thus be seen that the precession of the gyroscopes 1 and 2 will cause torques to be applied about the precession axes of gyroscopes 31and 32 in predetermined directions and in synchronlsm with the natural period of the ship. The levers 105, 106 and stop 112 above described are in the nature of a limit device which automatically stops the precession gear when the main gyroscopes approach the limit of their movement. This limit mechanism is, of course, not always brought into operation when the precession engine is controlled entirely through valve 69, but when a rough sea is encountered the .stop mechanism opcrates and stops the worm 49 irrespective of the position of valve 69.

Returning now to the action of valves 67 and 67 let us suppose that the amplitude of the roll of the ship is approaching the predetermined value. As this value is .within 1 would require a much more reached, port 123 in one or the other of valves 67 and 67 will be uncovered by the impact of rod .63 or '64 with valve rod or 65 (for instance) and air will flow through pipe 75 into one end of the small cylinder 124 forming a part of valve 74. The main piston 125 of valve 74 has secured thereto the piston 126 of cylinder 124 and preferably also a stop rod 127. The piston 125 and its attached piston 126 are normally held in,the position shown in the drawing by a compression spring 128, but when air is admitted through pipe 75 or 76 the plunger is forced to the other en of its stroke and the relation of the ports changed so that the air flowing in through pipe 72 will now flow through the recess in the plunger and through port 122 into pipe 77, while air flowing in pipe 73 will flow through port 129 into pipe 78. It will readily be seenthat this operation will reverse the connections between the recession valve 69 and the cylinder 79. ylinder 124 is provided with a graduated release valve 200 so as to permit a gradual, but steady escape of'air therefrom whereby the piston 126 will be slowly returned by spring 128, unless the cylinder is supplied at frequent intervals from valves 67, 67. Additional reservoirs 201 may be provided between the valves and the cylinder to avoid sudden movements of piston 126. It will be understood, that, as actually constructed, the various parts are made so that they can. be readily adjusted or thrown out entirely so that the apparatus may be used at times solely as a stabilizer, at other times solely to roll the ship through any desired angle. Also that, when used to maintain a definite amplitude of roll, that the amplitudemay be varied to suit the varying conditions encountered. In the electrical form of the invention, this adjustment is accomplished by shifting the position of contact 27, while in the other form it is secured by adjusting the position of valves 67 and 67' with respectto brackets-171 by. resetting the lock nuts 172 on bolts 173 by means of which thevalves are bolted to the brackets. (Figures 4 and 5.)

ong the many advantages secured by my invention are the increased accuracy of gun fire, as explained, and a marked reduction in the capacity of stabilizing apparatus required. Thus, to stabilize a battleship in a sea which would normally roll it 10, to

owerful stabilizing unit than that requirdil to maintain a uniform roll of 5. 1 In accordance with the provisions of the patent statute's, I have herein described the principle of operation of my invention, together with the apparatus, which I now con-- sider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by .other means. Also, while it is designed to use the various features and elements in the combination and relations described, some of these may be altered and others omitted without interfering with the more general results outlined, and the invention extends Similarly the stabilizing efl'ect only need be, or in a rough sea, would be employed, which effect would be brought into action when the roll exceeds a predetermined amplitude.

Having described my invention, what I desire and claimby Letters Patent is:--

1. The combination with a ship, of means mounted thereon for maintaining a roll of predetermined amplitude and gyroscopic governing means for causing said other means to act in the natural period of the shi 2 The combination with a ship, of means for exerting periodic rolling torques thereon, and means responsive to the amplitude of the ships roll for governing the action of said other means to maintain a rolling motionof predetermined magnitude.

3. The combination with a ship, of means for exerting rolling torques thereon, and means responsive tothe amplitude of the ships roll for changing the phase relation of the torques applied with respect to roll of the ship by substantially 180.

.4. The combination with a ship, of a gyroscope mounted therein for exerting periodic rolling torques thereon, and means responsive to theamplitude of the ships roll for changingthe direction of the torques applied with respect to the roll of the ship.

5. The combination with a ship, of a gyroscope mounted therein for exerting torques thereon, means for applying periodic torques on said gyroscope about its precessional axis, and means responsive to the amplitude of the ships roll for governing the synchronism of the torque on the gyroscope and the roll of the ship. I

6. The combination with a ship, of a gyroscope mounted therein for exerting torques thereon, means for applying periodic torques on said gyroscope about its prece'ssional axis, and means responsive to the amplitude of the ships'roll for governing the synchronism of the torque on the gyroscope and the torque exerted by the gyroscope.

the

7. The combination with a ship, of a gyroscope mounted therein for exerting torques thereon, means for applying periodic torques on said gyroscope about its precessional axis, fluid operated means for controlling the application of said means, and a governor responsive to the amplitude of the ships roll for controlling said fluid operated means.

8. The combination with a ship, of a gyroscope mounted therein for exerting periodic rolling torques thereon, and means responsive to the amplitude of the ships roll for changing the direction of the torques( aplied with respect to the roll of the ship and or applying a brake on the gyroscope.

9. The combination with a ship, of means for exerting periodic rolling torques thereon, a gyroscope mounted thereon for precession on rolling thereof, and means resonsive to a predetermined precession of said gyroscope for changing the direction of the torques applied with respect to the roll of the ship.

10. The combination with a ship, of a gyroscope mounted thereon. for exerting periodic rolling torques thereon, a second gyroscope for controlling said first gyroscope, and means responsive to a predetermined precession of said second gyroscope for changing the direction of the torques applied by the first gyroscope with respect to the roll of the ship.

11. The combination with a ship, of a gyroscope mounted therein for exerting.

torques thereon, means for applying periodic torques on said gyroscope about its precessional axis, a second gyroscope, means responsive to precession of said gyroscope for controlling said means, and means responsive to a further precession of said gyroscope for reversing the operative connections between said controlling and said torque applying means.

12. The combination with a ship, of a gyroscope mounted therein for exerting torques thereon, means for applying periodie torques on said gyroscope about its precessional axis, comprising a continuously driven motor, reversing gearing between said motor and the gyroscope, fluid operated means for shifting said gearing, a second gyroscope, and means responsive to a predetermined precession of the second gyroscope for operating said fluid means.

13. The combination with a ship, of a gyroscope mounted therein for 'exerting torques thereon, means for applying periodic torques on said gyroscope about its-precessional axis, comprising a continuously dr ven motor, reversing gearing between said motor and the gyroscope, fluid operated means for shifting said gearing, a second gyroscope; means responsive to a predetermmed precession of the second gyroscope for operating said fluid means, and ther means responsive to a predetermined precession of the first gyroscope for shifting said gearing irrespective of said other responsive means. r

14. The combination with a ship' of a gyroscope mounted thereon for precession relative thereto, means for exerting periodic rolling torques on the ship, a valve actuated by precession of the gyroscope, fluid pressure means governing the application of said torques, a reversing valve in the connections between said other valve and said fluid pressure means, and a limit valve actuated only upon a predetermined precession of said gyroscope for controlling said reversing valve. 15. The combination with a ship, of a gyroscope mounted thereon for precession relative thereto, means for exerting periodic rollin torques on the ship, a member displacea le by the precession of said gyroscope yielding means for returning said member, means whereby said return is retarded, and means responsive to the position of said member for controlling said rolling means, a valve actuated by precession of the gyroscope, fluid pressure means governing the application of said torques, a reversing valve in the connections between said other valve and said fluid pressure means, and a limit valve actuated only upon a predetermined precession of said gyroscope for controlling said reversing valve.

16. The combination with a ship, of a gyroscopemounted thereon for precession relative thereto, centralizing means for said gyroscope, means for exerting periodic rolling torques on the ship, a valve actuated by precession of the gyroscope, fluid pressure means governing the application of said torques, a reversing valve in the connections between said other valve and said fluid pressure means, a limit valve actuated upon a predetermined precession of said gyroscope for shifting said reversing valve, and a yielding and retarding means for slowly returning said valve.

17. The combination with a ship, of means for exerting rolling torques thereon alternately in opposite direct-ions, including a control device for said means for causing reversal of said torques when the roll of the ship reverses, and means responsive to an increase in amplitude of the ships roll beyond a predetermined amount, for causing said control means to out out said torque applying means until said amplitude returns to normal.

18. The combination with a ship, of means for exerting rolling torques thereon in a direction to stabilize the ship, and means responsive to a decrease in the amplitude of the ships roll for throwing said means out gyroscope mounted therein for exertingperiodic rolling torques thereon, and means responsive to an increase in amplitude of the ships roll beyond predetermined amount for rendering said gyroscope inoperative to roll the ship until said amplitude returns to normal.

20. The combination with a ship, of a gyroscope mounted therein for exerting rolling torques thereon to roll the ship, and means responsive tothe rolling of the ship beyond a predetermined amount, for rendering said gyroscope operative-to stabilize the ship.

21. The con'ibination with a ship, of means 'for exerting rolling torques thereon, a gyrosco e mounted thereon for precession on 'rol ing thereof, and means responsive to a predetermined precession of said gyroscope for governing the action of said means.

22. The combination with a ship, of a gyroscope mounted thereon for exerting rolling torques thereon, a second gyroscope for controlling said first gyroscope, and means responsive to a predetermined precession of said second gyroscope for rendering said gyroscope inoperative to roll the ship.

23. The combination with a ship, of a means thereon for applying rolling torques on the ,ship, a control gyroscope mounted for precession on rolling of the ship, means for governing the action of said rolling means from said gyroscope, and means re-- sponsive to the extent of precession of said gyroscope for altering the action of said governing means. s

24. The combination with a ship, of a means thereon for applying rolling torques on the ship, a control gyroscope mounted for precession on rolling of the ship, means for governing the act-ion of said rolling means from said gyroscope, and means responsive to the extent of precession of said gyroscope for reversing the action of said governing means to cause the torques exerted by sald first means to oppose rolling.

25. The combination with a ship, of a stabilizing means thereon, a governor for said means responsive to the amplitude of ships roll, and means connecting said governor and stabilizing means adapted to prevent operation of said stabilizing means unless the roll of the'ship exceeds a predetcrmined amplitude.

In testimony whereof I have aflixed my signature.

ELMER A. SPERRY. 

